In Geneva on Saturday, world powers attempted a vague showof unity by committing to support for a transitional government.But diplomats led by United Nations envoy Kofi Annan failed tobridge differences between the West and Russia - backed by China- on whether or not that meant that Syria's president must go.

In any case, neither Assad's government nor his variousopponents have shown great interest in such an accord. Instead,both sides look to be digging in for a long, winner-takes-allstruggle, ramping up the violence and turning to foreignsponsors in a confrontation that could last months, or years.

A meeting in Paris this coming Friday of the loose allianceknown as the Friends of Syria is likely see the United States inparticular come under greater pressure from Turkey and theSyrian opposition's Arab allies - principally Saudi Arabia andthe Gulf state of Qatar - to increase its help for the rebels.

Washington has long worried about the wisdom of backingSyria's opposition, which it sees as ill-organised, disparateand much too close to al Qaeda-linked militants. It has limitedaid to "non-lethal" equipment, such as radios. And, in anelection year, the White House is anxious to avoid anything thatmay look like an Afghan-style, open-ended military intervention.

Yet it also acknowledges that some of its allies have optedto get more involved in actively support the rebel campaign.

"We're concerned about pouring more weapons into an alreadyover-militarised situation," U.S. State Department spokeswomanVictoria Nuland said on Monday. "We've made our decision.

"Other countries are making other decisions. Our goal now istrying to stay coordinated."

Though public details on aid to the rebels are scant, U.S.officials say Saudi- and Qatari-funded weaponry is finding itsway, mostly via Lebanon, into Syria, to be used against Assad,whose Alawite religion and alliance with Shi'ite Iran distancehim from the Sunni Muslims who run most other Arab states.

Some fear foreign powers may simply be making things worse.

"The unfortunate truth is that it's a very difficultsituation and it's hard to know where to go from here," said AriRatner, a former State Department Middle East adviser to theObama Administration and now a fellow at the Truman Project onNational Security. "Other countries are being dragged into aproxy war ... which may in itself help perpetuate the violence."

On Monday, U.N. human rights chief Navi Pillay complainedboth sides were receiving more and more weapons, creating moreviolence - though she did not say who was sending them. Assadhas bought much of his weaponry from longstanding ally Russia.

The Western powers remain publicly committed to other toolsto weaken Assad's grip on power - primarily financial sanctions.

U.S. officials say they hope Syria's opposition will endorsethe Geneva plan for sharing power with Assad loyalists when theymeet in Paris on Friday, though for now opposition spokesmanhave been asking instead for weapons. Washington has flatlyrefused, although it says it cannot stop others from offering.

Compared to Assad's forces - increasingly using not justtanks and armoured vehicles but also artillery and attackhelicopters - the Free Syrian Army remains desperatelyunderequipped, capable of little more than hit and run attacks.

While they have fought on for months in pockets such asHoms, where they benefit from weapons smuggled across the borderfrom Lebanon, they can still barely hold ground. Nor do theyhave many military options when government forces withdraw fromopposition areas only to then pound them with artillery shellssupplied from either Russia or Iran.

BUFFER ZONE

Yet for all the concern about contributing to furtherbloodshed, some who wish to see Assad gone see arming the rebelsas a better option than simply waiting, or than any form ofdirect Libya-style campaign committing warplanes or even troops.

Turkish action in the past week - following the shootingdown of a Turkish reconnaissance jet by Syrian air defences -may be the clearest example yet of foreign action to redraw thelines of battle in favour of the rebels.

Last week, Turkey moved heavy artillery and anti-aircraftmissiles up to its border with Syria, publicly warning Damascusthat any forces which approached Turkish territory might beliable to attack.